Dunbuy Sea Arch, Aberdeenshire.
Natural sea arches are the result of coastal erosion.
Wave power acts against the land, exploiting weaknesses in the geology.
These beautiful formations are much photographed around the world
as windows to sunsets and sea spray.
Each arch is at a different stage in its lifespan, from formation to collapse.
As such, they are truly unique.
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Share a picture that means UNIQUE to you.